Finally tonight here that uncomfortable moment on the plane and we're not talking about turbulence here. Abc's david wright on the stranger who suddenly asleep in her neighbor's lap and so borrow a line from john quinones, what would you do? Reporter: As if the patdowns and the meltdowns and the delays weren't indignity enough, at 35,000 feet, your personal space is precious. So when a perfect stranger encroaches fast asleep? Major party foul. "I don't know what to do!" Steve collum mouths. As soon as we lifted off she started drifting my way. She immediately became dead weight and pretty much kind of collapsed on me. Which, we all know, can be nice if it's someone you love. But otherwise kind of awkward. She just was not waking up. So eventually I tried coughing loudly and things like that to kind of startle her. Reporter: Like the seat back and the storage bin, it's part of the etiquette of shared spaces. What should you do? We asked author and flight attendant. Her advice, ring the call button, ask for help. You could create a buffer zone using blankets and pillows or try politely shaming them. What he did was film her and his reactions and post the video to youtube. It went viral, maybe the best revenge at all. She probably won't sleep on a plane again and I won't sleep on a plane again. Reporter: He knows the next time it could be him. Finally he says, finally off of me. David wright, abc news, los angeles. The advice, call for the flight attendant. Building a barrier was a little late for that.

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